This is a balsa tower made for the 'crow shot' in 'Fellowship of the Ring', when Saruman's crows return to Isengard and fly into the underground caverns to report to their master!
It was made and painted by Alasdair Mahar, and as a joke it incorporates a small Soviet-style 'space pod' built by fellow studio modeller Alan Pilkington from a plastic Air New Zealand drinking cup! There are also two resin fuel-tank castings; leftovers from a model I was making at the studio in my spare time.
I know it was dressed into the set and shot, but I haven't been able to spot it on-screen myself. Maybe someone can spot it on the BluRay. Or maybe it was covered up by digital crows!